Dental casting machine



May 13 A, 1924.

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May 13 1924.

T. A. MlxoN DENTAL CASTING MACHINE Filed Sept. 1`o

1921 3 Sheets-Sheet 2 n N NV w N www w IN 0. NM N 7M w M M M ne d@ N w wNNNN N May 13, 1924. i 1,493,692

T-. :A. MlxoN DENTAL CASTING MACHINE Filed Sept. l0 1921 I5 Sheets-Sheet5 TEIDMAS A. ,'If`, @E ATILMTA, GEGRGIA.

DENTAL {IiiSTNC-f MACHNE.

' Iapplication nlei September 10, 1921. Serial 1%' o. Naas-t.

To al? @alzo/m t may concern: forated reducing coupling 4 threaded onthe Be it known that l, THOMAS A. Minori, a exterior to engage thethreaded walls of citizen of the United States, residing at said hole 3and having a central depression Atlanta, in the county of Fulton andState 5 interiorly threaded for engaging the hola of Georgia, haveinvented certain new and W threaded member 6 ofan adapter 7` 60 usefulImprovements in Dental Casting Mawhich may be removed quickly if desiredby chilies; and I do hereby declare the followunscrewing it, inorderthat, in place of the ing to be a. full, clear, and exactdescription sald adapt-er 7, atlask or casting cup 70 of of theinvention, such as will enable others large size may be fitted directlyinto said 10 skilled in the art to which it appertains to Cavity 2; Theadapter 7 has an orifice 8 @5 make and use the sume, extendingcompletely through it from the This invention relates to dental castingtop Surface to the lower end of the member machines or the like, andmore particularly G. The 0111301 edge 9 Of the adapter' I'SSS. tocasting machines of this type in whichy snugly upon the top surface ofthe base 1 l5 air pressure is applied on top of thel casting alonnd themargin of cavity 2. ln the top 70 during the casting operation andsimultane- 0f lille adapter is a Countersink or cavity 10 ously air iswithdrawn from the mold. ildilpld t0 rece-ive a flange 11 of a castingThe Object of this invention is t0 make cup 12. The casting cup 12, orthe'like, is

perfect Castings of gold inlays, bridges` to contain themold material inwhich the crowns, abutments, and partial, or full metal mold 1s formedand in this mold the metal dentures, used in the dental profession; ort0 be Cast Ina-y be melted, as by a blow pipe in the jewelry trade toenable various artiflame. 'y cles of precious metal, where a wax orother Connected to the lower reduced portion of form of disappearingpattern is used. to be ille reduc-111g COUpling 4 rby the unioncouaccurately @ist pling 13 is a pipe 14 the other end of which 30 Theinvention comprises a mold flask, or iS COIlneCted by a similar coupling15 to a casting cup, in combination with mechanism threaded hollownipple 16 projecting from for applying nir pressure to the top 0f thethe Of a. SllCtlOD Pump `Cylinder 17, casting in the mold andSimultaneously thus establishing communicationbetween the withdrawingair from the mold cavity pump cylinder and the casting cup. The 35through the bottom of the cup. t com- Pump Cylinder 17 may be securedfirmly to prises, also, various subcombinations and'deille tOp 0f thebase 1 by means of bolts or tails of construction more fully set forthin piller fastenngs passed through anges 18 the ensuing description,illustrated in the 1 I1t0 the bilSn l. In the embodiment of theaccompanying drawings and defined iu the invention described the cavity2 is located 90 appended claims. substantially along the center line ofthe In the accompanying drawings in which base l adjacent 011 @11dtlleleOf, While the' like reference characters designate like parts pumpcylinder 17 is secured to said base at throughout the Several views; oneside of the center line for a purpose to 40 Figure 1 is a. top plan viewof the combe presently explained. Rising on opposite 95 plete apparatus;Sidesfof the cylinder 17 are upright guiding Figure 2 is a longitudinalsection on the standards 19 which, in the" present instance, irregularline 2-2 of Figure 1; are utilized for securing the pump cylinder Figure3 is an elevation of the apparatus 17 down upon the 'base 1. as shown,the

viewed from the right hand side of Figures lower ends of said standardsbeing reduced, 100

1 und 2; passed through perforations in flanges 18 Figures 4. 6 and 7are details of flasks, and threaded into base 1. Within the cylorcasting cups, with associated equipment. inder 17 is a ,piston 20,suitably packed, and

In the. particular embodiment of my inattached to a piston rod 21, whichextends vcntion illustrated in Figures 1 to 3, nuupward through acentral opening in the 105 meral 1 indicates a base, said 'base having acylinder head 22 secured to. the top-'of the cavity 2, preferably in thelongitudinal cencylinder in any approved manner, but shown ter line ofthe base and circular in form as as screw` threaded thereto. Above thecylshown, the bottom wall of said cavity havinder head 22 the piston rod21 may be cone5 ing a threaded hole at 3 closed by a pernected toaU-shaped yoke 23, the limbs 1,10

23*1 of which extend downward, parallel with each other, on oppositesides of the piston, and have perforated terminals 24 extended at rightangles, the standard 19 passing through said perforated terminals `24vand serving as guide standards forthe yoke. Coil compression springs 25are disposed between the perforated terminals 24 and the base flange ofthe pump cylinder, said sirings exerting their elastic. force to pushtlie yoke 23 upward and thereby carry the piston 20 upward. Perforations22a formed in the cylinder head 22, allow free esc-apeA of air. Themeans forsecuring the yoke 23 to the piston rod comprises a collar 26 0nthe piston rod engaging the under side of the yoke; a large washer 27engaging the top side of the yoke, said washer being locked down by anut 28. Secured tothe top of the piston rod v21 is a suitable handle 29Which may receive the pressure of the hand to force the pump pistondownward.

Rising from that end of the base l which is opposite the cavity ordepression 2 is a pair of bearing lugs 30, 30, spaced equally onopposite sides of a center line that intersects the axis of cavity 2,between which is pivoted a cover and trip-carrier arm 31 by means ofconical bearing pivots 32 or by other suitable means. The said carrierarm 31 when in operative position extends upward from its pivotalbearing and then turns substantially at right angles and extends overthe base l in substantial parallelism therewith. At the end of saidcarrier arm 31 is a suitable hand-hold 33 by means of which the arm maybe manipulated. As shown clearly in Figure 2 the arm is hollow for aportion of its length providing an air chamber as illustrated at 34.Tapped into the arm, preferably at the end ofthe chamber y34 nearest thepivot, is

a fluid conductor 35 for the purpose 0f admitting air under pressureinto the hollow portion 34 of the arm. In order to regulate the pressureof the air flowing into the chamber 34 I may provide a suitable reducing'valve 36; and in order to determine the pressure of the air enteringthe chamber 34 of the hollow arm I may provide any suitablepressuregauge 37. The end of conductor 34 opposite its connection to thelever is adapted to' be coupled to a flexible pipe leading from a sourceof air or other gas under pressure. Communicating with the chamber 34preferably at its upper end and carried on the under side of the arm 31is a tubular extension 38 fitted air tight t0 the hollow arm and havinga conical or other suitable valve seat 39 at its upper end. Telescopedinto the tube 38 is a second tubular member 40 which may have aspheroidal end 41, engaged by a coupling member 42 having acorrespondingly curved opening and an interiorly screw-threaded maaeaaflange 43 adapted to be seated over the spheroidal end and to be coupledwith an exteriorly threaded flange `44 on a cover plate 45 which isprovided with an asbestos or other -refractory centrally perforatedpacking 46 on its under side. The interior of the flange 44 is alsocurved spherically and engages the exterior of the head 4l. Thus, thecover plate 45 is connected by means of the coupling 'member 42 to thehead 41 of the tubular section 40 so that it has a self adjustinguniversal movement thereon. A refractory nipple 41 may be seated inthelower end of the tube section 40. A coil spring 47 disposed betweenthe coupling member 42 and the lower end of the extension 38 keeps theSaid members 38 and 40 extended, relatively, so that the valve 48, whichis adapted to seat on the valve seat 39, heretofore referred to, isclosed. The said valve 48 is provided with a conical head, a stem 49, ashoulder and a threaded extremity 51, the said stem 49 below theshoulder 50 being free to, slide a limited extent in a perforateddiaphragm or bridge 52 which is connected to the tubular section 40. Thesaid bridge 52 may be a plug having perforations therethrough, an`integral web, or any other suitable construction, fixed to the tubesection 40, which will permit the passage of air. To the threadedextremity 51 of the shank 49 of the valve is secured a nut 51,preferably relatively heavy, and tending to move the valve 44 toward itsseat. By this construction the spring 47 will extend the tubes 38 and40. normally, until the extension is checked bv engagement of the headof the valve 48 with the seat 39, thus maintaining the valve closedexcept when pressure is applied to the free end of the tube section 40.

A pull spring 53, having one end attached to lug- 54, on lthe base 1.and the other end attached to the arm 31 above its pivot at 54a exertsits tension t0 swing the arm upward about its pivotal connection withbearing lugs 30, 305 to lift the arm 31. .In order to limit the upwardmovement of the arm 31. a quadrant member 55, formed on 0r secured toit, extends below the pivotal axis at one side, said quadrant memberhaving' a hole 56 and a lug 57, separated about 9() from each other.lVhen the arm is down. as it is in casting position, a spring-actuatedlatch'pin 58 carried by and extending through the bearing lug 30a is inalinement with the hole 56 and will lock the arm in that position. Whenthe latch pin 58 is pulled outward the tension of spring 53 moves thearm upward until the lug 57 engages with one edge of the bearing lug-30n and brings the arm to rest with the handle 33 projecting upward; A

` A trip finger 60 is secured to arm 31, in such manner as to beadustable transversely of the arm in a plane perpendicular to the basel, that is, when lthe arm is in its lowered position and the baseis-horizontal, the linger G() may be adjusted vertically. its shown, thearm 31 is irovided with an opening at one side of its longitudinalcenter within which the finger may slide longitudinally of itself, and aset screw 61 is )rovided for clamping the finger in the desiredposition.

Pivoted on the cylinder head 22 is a latch having an arm provided with alatch head 62 and a trip arm 63 extending substantially at right angles`to the head-carrying arm inta the path `of the end of the trip finger60 on the arm 3l when said arm 1s brought down to operative position. Aspring such as 64 maintains the latch constantly in latching position.The latch head 62 engages overtlie washer 27, :or other suitablelatehengaging member, carried by some part connected to the piston rod 21.

Referring now to Figures 1, 2 and3, the operation of the means thus fardescribed 1s as follows: The mold having been suitably.

formed in the castingfcup 12 in the known. manner, the metal is fused inthe mold by a blow pipe. At that time the arm 31 is in elevated positionand suction um piston 20 is locked down, in the position s viovvn inFigures l and 3, byV the latch, the pump piston having been previouslydepressed by pressure of the hand exerted upon the handle 29. At thistime the tube sections 38 and 40 are extended by spring 47 and the valve48 is closed upon the seat 39. As soon as the metal has been fused andrun into the mold cavity thehand-hold 33 of the arm 31 is seized and thearm 31 pulled downward, bringing the cover 45 on top of theflask orcasting cup 12. The relative position of the top of the casting cup withrespect to the rest of the mechanism describedv is suoli that the tube40 will be pushed slightly into the tube 38 and the lvalve 48 raisedfrom its seat by reason of the engagement of the bridge or web 52 withshoulder 50p on the valve stem letting air under pressure flowdownwardthrough the tubes 38 and 40 and through the orifice in the endof the tube 40, cover cap and packing, into the mold. The

cover 45 will adjust itself absolutely to the released the spring 25bearing upon the yoke 23 moves the piston upward, the air above thepiston escaping lthrough the openings 22g. rllhuspressure is reduced onthe under side ofthe piston and air drawn from the mold so that no aircan be encased' or occluded in the duid metal being cast or prevent thefluid metal from entering the finest interstices of the mold. Pressureof the compressed air on the top of the metal, and simultaneousexhaustion of the air through the mold material, insure the perfectfilling of the mold contour so that' the negative contour of the mold isreproduced exactly and with the greatest nicety asa positive in thecasting.

In order to accommodate molds of different size and adapt casting cupsor fiasks of diderent size to this apparatus, a variety of cups withappropriate adapters have been provided. ln case a very large flaskorcasting cup, such as is shown at 7 0, is to be used, the adapter 7 isremoved, the cup 70 seated in the cavity 2 and the adapting cover 71applied to said cup 70, The said cover has a central opening surroundedby a flange' 72 of lesser diameter than the cover 45 so that the samecover 45 which is adapted to fit over a smaller casting cup may beadjusted to this large'cup 70. The height of the cup 7 0 plus the heightof the cover 71 is equal to the distance from the bottom of cavity 2 tothe top ofcup 12 seated on vadapter 7. In case it is desired to use acasting cup 73, which is still smaller than the cup 12, a second adapter74 is fitted onto the adapter' 7. On the under side of the adapter 74 isa flange 75 surrounding an opening in the adapter, which flange fits thecountersink or cavity 10 in the upper side of the adapter 7; and ontheupper side of the adapter 74 is a cavity which lits a flange 76formed around the opening in the bottom of said cup 73. By thisconstruction the cup 73, which is shallower than the cup 12, may bebrought with its upper edge to the same height above the base 1 as wasthe cup 12 seated on the adapter 7. In the same manner a still smallercup 77 of less height' than the cup 73 may be brought into position sothat its upper edge will be the same distance above the base 1, as thetop of the cup 12 seated yon the adapter 7 by adding a second adapter78, as indicated in Figure 7. Thus, different sizes of casting cups bythe use of adapting bases or adapting covers may be utilized on the samemechanism Without making any other adjustments.

Having described my invention-in such manner as to enable those skilledin the art to make and use the same what I claim and desire-to secure byLetters Patent is:

1. In casting apparatus, a movable hollow carrier adapted to beconnected with a source of fluid under pressure, a perforated flaskcover having communication with the interior of said carrier, auniversal joint between said carrier and said cover, and a valve forcontrolling the flow of fluid under pressure to said cover.A

2. In casting apparatus, a movable, hollow carrier adapted to beconnected to a source of fluid under pressure, a perforated flask coverhaving conn'nunication with the interior of said carrier, a universaljoint between said carrier and cover, a normally closed valvecontrolling communication between the carrier andthe perforated cover,and means for opening said valve responsive to pressure of the cover onthe flask.

3. In casting apparatus, a movable hollow carrier adapted to beconnected to a source of fluid under pressure, a longitudinallyyieldable tubular member communicating with the hollow carrier, aperforated cover plate carried by the end of said tubular member, avalve for controlling the passage of fluid from the carrier into saidmember, and means actuated by a yielding movement of said member forunseating said valve.

t. In casting apparatus, a movable hollow carrier adapted to beconnected to a source of fluid under pressure, a tubular extension fromsaid carrier, a valve seat between said extension and carrier, a tubulartelescoping section movable longitudinally of said eX- tension, a valveadapted to engage said valve seat, connections between said telescopingsection and valve, a perforated flask cover-carried on the end of saidtelescoping section, and a yieldable means for extending saidtelescoping section.

5. In casting apparatus, a movable hollow Vcarrier adapted to beconnected to a source of fluid under pressure, a tubular extension fromsaid carrier, avalve seat between said extension and said carrier, atubular telescoping section movable longitudinally of said extension, avalve adapted to engage said valve seat, connections betweenv saidtelescoping section and valve, a )erforated flask covei` connected tothe end o said telescoping section, and a coiled compression springsurrounding said telescoping section between the endof the extension andthe flask cover. w

G. In casting apparatus, a movable hollow carrier adapted to beconnected to a source of fluid under pressure, a tubular extension fromsaid carrier, a valve seat between said extension and said carrier, atelescoping section slidably connected with said extension, a valveadapted to be seated in said .valve seat, connections between saidtelescoping section and valve, a perforated cover universally jointed tothe free end of said telescoping section, and a coiled compressionspring surrounding said section between the cover and the end of theextension.

7. In casting apparatus, a movable hollow carrier adapted to beconnected to a source of fluid under pressure, a perforated flask ,coveruniversallv connected thereto and having communication with the interiorthereof, means to control the passage of fluid under pressure to saidcover, and a reducing valve for regulating the pressure of the fluid intlie carrier.

8. In a casting apparatus, a movable hollow carrier adapted to beconnected to a source of fluid-under pressure, a perforated.

flask cover universally connected therewith and having communicationwith the interior thereof, means to control the passage of fluid underpressure to the cover, a reducing valve for regulating the pressure offluid in the carrier arm, and a pressure gauge adapted to indicate thepressure in said carrier.

9. In casting apparatus, a base adapted to support a flask, a carrierarm pivoted to said base, a perforated flask cover uni-` versallycarried by said carrier arm, means for controlling the passage of fluidunder pressure to said cover, and means for norlmally elevating said armwith a yielding force to remove the cover from the flask.

lO. In casting apparatus, a base adapted to support a flask, a carrierarm pivoted to the base, a perforated flask cover carried by saidcarrier arm, and means to control the passage of fluid to said cover, aspring normally acting to elevate said carrier to remove the cover fromthe flask, and a device to hold the arm in its lower position with thecover pressed upon the flask.

11. In casting apparatus, a base adapted to Sustain a flask, a pair ofbearing lugs elevated from the basea carrier arm pivotetd between saidbearinglugs and carrying a perforated flask cover, means for controllingthe passage of fluid under pressure to said cover, a spring arranged toexert its tension to elevate the arm, a quadrant on the arm extendingbelow the pivot thereof, a stop on said quadrant adapted to engage oneof said lugs when the arm is elevated, and cooperating latch means onsaid quadrant and one of said bearing lugs adapted to hold the arm inits lowered position with the cover pressed upon the flask.

12. In casting apparatus, a base having a perforation and adapted tosupport a flask over said perforation, a carrier arm movably mounted onthe base, a flask cover mounted on said carrier, a pump cylindervmounted on said base, a conduit connecting said cylinder with theperforation in the base, a piston in the cylinder, yieldable :means formoving said piston, a latch for `holding said piston against the tensionof said yieldable means, and a trip carried by the arm arranged torelease the latch at the `time the cover is pressed upon the flask.

13. In casting apparatus, a base havin a perforation and adapted tosupport a flasl over said perforation, a suction pump cylinder mountedon the base, a conduit connecting the cylinder with the perforation inthe base, a piston in said cylinder, a piston rod connected to saidpiston, a yoke ysecured to said piston rod, means for guiding the yoke,compression spring means surrounding the guiding means and acting uponthe yoke to operate the piston, a latch for holdin-g the pistonretracted and the spring means under compression, and means to releasethe latch.

14. In casting apparatus, a base having a depression, an orifice in saiddepression, a suction device kmounted on the base, a con.- duitconnecting Said suction device with the orifice in said depression, aremovable adapter having a central perforation adapt ed to communicatewith said oriiice, said adapter being adapted to receive a flask on itsupper surface. A

In testimony whereof aiiix mv si nature.

THOMAS A. M1 ON.

